Indicator for use with calipers, scribing-blocks, and the like.



J. H. GRANT. INDIGATOR FOR USE WITH OALIPBRS SGRIBING BLOCKS, AND THELIKE.

APPLICATION FILED AUG. 8

Patented Feb. 23, 1915.

//7 uer 'for' mfncoaes THE NORRIS PETERS 60.. PHOTC LITHO., WASHINGTON,D. C.

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JAMES HENRY GRANT, OF EAST DULWICH, LONDON, ENGLAND.

INDICATOR FOR USE WITH CALIPERS, SCRIBING-BLOCKS, AND THE LIKE.

' Application filed August a, 1912.

To all whom it may concern:

Be it known that 1, JAMES HENRY GRANT, a subject of the King of GreatBritain and Ireland, residing at School House, Heber Road, East Dulwich,London, England, have invented certain new and useful Improvements inIndicators for Use with Calipers, Scribing-Blocks, and the like, ofwhich the following is a specification.

This invention for improvements in indicators for use with calipersscribing blocks and the like relates to indicators in which the movementof a spring controlled member is magnified and indicated on a scale by alever, and consists in mounting the lever on a knife edge fulcrum andoperating it by another knife edge so that these two points can bebrought close together and thus a great multiplication obtained of themotion of the operating edge with a lever of small dimension.

Another feature of this invention is the mounting of the fulcrum adjustably in order that the position of the spring controlled member maybe regulated or adjusted without altering the position of the pointer onthe scale.

A further feature of this invention consists in mounting the fulcrumadjustably in order that the proportions of the indicating lever may bevaried.

The accompanying drawing illustrates various practical forms ofindicators constructed according to the invention.

Figures 1 and 2 are respectively a sectional elevation and an outsideplan of an indicator provided with an adjustable knife edge fulcrum.Fig. 3 is a view showing the same attached to a pair of calipers. Fig.4: is a sectional elevation of an indicator with a modified form ofadjustable fulcrum. Fig. 5 is a similar view of an indicator in whichthe fulcrum is fixed. Fig. 6 shows the spring controlled member on anenlarged scale. Fig. 7 is a detail front elevation of the pin whichconnects the indicating hand with the contact stud.

In the arrangement shown in Figs. 1 to 3 the indicating lever a isfulcrumed about a knife edge 6 of steel which is secured to the block 0.This block 0 is pivoted at d to the casing c in which it forms adistance piece and is adapted to be moved by a cam f carried on screwand nut g This cam f is housed in a slot in the block 0 so that whenSpecification of Letters Patent.

PatentedFeb. 23, 1915.

Serial No. 714,113.

rotated it can raise and lower the block together with the knife edgefulcrum.

When the position of the knife edge Z) is to be adjusted or regulated,the cam f is rotated thus turning the block 0 about the pivot d whilethe knife edge 6 slides on the face of the spring controlled member h.The spring controlled member h is slotted at its upper end i to receivethe end of the lever a which is secured thereto by the pin asillustrated inFig. 6. The pin j has its sides notched as shown in Fig. 7and is inserted through an opening in the lever a which is sufficientlylong to permit this pin to have its larger lower end passedtherethrough, and said pin is then turned to dispose its contracted neckportion in the opening of said lever or hand a whereby the shouldersformed on opposite sides of the pin at the upper end of its neck, willengage the upper face of said lever and hold the pin in operativeposition. The lever a is also provided at the rear end of this openingwith a knife edge a which bears on the pin j (see Fig. 6). The openingor slot in the upper end of the member A through which the lever apasses is provided on its upper and lower walls with knife edges k whichpermit the pivotal movement of said lever a in a vertical direction.This spring controlled mem her it is slidably mounted between the end ofthe casing e and the block 76 and carries an enlarged head 72. at itslower end. This block 70 carries the spring Z which normally holds theindicating lever in the zero position. One side of the case 6 extendsfarther than the other and is graduated to form a scale m over which theindicating lever moves.

In attaching the indicator to calipers or scribing block the thumbscrews or nuts .9 and g are used.

In the arrangement shown in Fig. 4: the knife edge fulcrum is formed aspart of the block 0 and thus turns with the block about the center 01when adjusted by the cam f. In this way the proportions and thus thesensitiveness of the indicating lever can be varied.

Fig. 5 shows a modified form of construction in which a fixed knife edgefulcrum is employed.

By means of this indicator small differences in dimensions may be shownand measured.

What I claim and desire ters Patent is 1. An indicator for use withcalipers and the like comprising a casing, a slidable contact studcarried thereby and provided at its inner end with aslot having a knifeedge, an indicating hand pivotally supported in said slot, a knife edgebearing on said hand adjacent its pivotal connection With said slidablecontact and a spring for resisting the movement of the hand in onedirection.

2. An indicator for use With calipers and the like comprising a casing,a slidable contact stud carried thereby and provided at its inner endWith a slot having a knife edge, an indicating hand pivotally supportedin said slot, a spring for resisting the movement of said hand in onedirection, and means for co-acting With said spring for inkdicating themovement of said slidable mem- 3. An indicator for use with calipers andthe like comprisinga casing, a slidable con tact stud carried thereby,and provided at its inner end with a slot having a knife edge, anindicating hand pivotally supported in said slot, a knife edge bearingon said hand adjacent its pivotal connection with said slidable contact,a spring for resisting the -movement of said hand when pressure isexerted on the outer end thereof, and means for permitting shifting ofthe fulcrum of to secure by Let- I said hand.

I 7 Copies of this patent may be obtained for 4:. An indicatorcomprising a casing, a

slidable member supported thereby, an indicating hand pivotallysupported by said slidable member, a spring bearing against said hand toresist its movement in one direction, a knife edge bearing on said handadjacent its pivotal connection with said slidable member, a blockpivoted to said casing and supporting said knife edge, and means adaptedfor angularly adjusting said block on its pivot.

' 5. An indicator for use with calipers and the like comprising acasing, a slidable contact stud carried thereby and provided at itsinner end with a slot having a knife edge, an indicating hand pivotallysupported in said slot, a block having a knife edge bearing on one sideof said hand adjacent its pivot, and a spring bearing on the oppositeside of said hand remote from its pivot.

6. An indicator comprising a casing, an indicating hand, a block aivotedto the casing and having a knife e ge bearing on one side of said hand,a spring bearing on the opposite side of said hand, a cam adapted toadjust the block about its pivot, and means pivotally connected to saidhand for angularly adjusting it on said knifeedge against the tension ofsaid spring.

In testimony whereof I have afiixed my signature, in presence of twowitnesses.

JAMES HENRY GRANT. l/Vitnesses:

H. D. JAMEsoN, TRACY LAY.

five cents each, by addressing the Commissioner of Patents,

Washington, D. G.

